Unfolding Models for Asymmetric Dissimilarity Data With External Information Based on Path Structures

This article contains asymmetric dissimilarity data which is observed in various situations. In asymmetric dissimilarity data, dissimilarity from subject i to j and from subject j to i are not the same necessarily. Asymmetric multidimensional scaling (AMDS) is a visualization method for describing the asymmetric relations between subjects, given asymmetric dissimilarity data for subjects. It is sure that AMDS is a useful tool for interpreting the asymmetric relation, however, existing AMDS cannot be considered for the external information, even if the external information of the same subjects for the asymmetric dissimilarity data is given. If the estimated coordinates can be interpreted from the loading matrix for the external information like principal component analysis (PCA), the AMDS become more useful. This is because we can interpret the relation between the estimated asymmetries and the factors of the external information on the low dimensions. In this article, we proposed new AMDS with external information. In addition to that, the proposed method can consider the path structure for variables like SEM.

Switch preference analysis by the drift vector method

The matrix of switch preference data (e.g. one’s preference for brand j, given that one has already defined his/her first choice for brand i) is not symmetric. The averaging of appropriate off-diagonal proximity entries for such data leads to the loss of information, hence the necessity to use appropriate methods for asymmetric data. Among the chosen methods of asymmetric multidimensional scaling, particular attention was paid to the drift vectors method. This method enables to present simultaneously on the perceptual map both the configuration of points representing the analyzed objects and the vectors indicating the direction and the strength of changes in the respondents preferences.